Vacuum thread trimmer

ABSTRACT

A vacuum thread trimmer for attachment to a conventional sewing machine including a vacuum box connected to a vacuum machine with the vacuum box having a reciprocating cutter mounted therein and driven by an electric motor suspended below the sewing machine table. The vacuum box is hollow and the cutter is hollow so that as to permit the severed thread to pass therethrough to the suction outlet.

United States Patent [191 Bray [111 3,815,533 5] June 11, 1974 1 VACUUM THREAD TRIMMER [76] Inventor: Murel B. Bray, El Paso, Tex.

[22] Filed:- Feb. 6, 1973 [21] Appl. No.: 330,051

[52] US. Cl. 112/252, 112/D1G. 1

[51] Int. Cl D051) 65/00 [58] Field of Search 112/122, 129, 130, 252, 112/D1G. 1

[56] References Cited UNITED STATES PATENTS 2,356,378 3/1944 Capolupo 112/D1G. 1

2,661,519 12/1953 Rubin 112/D1G. 1

2,722,728 11/1955 Stout 112/D1G. 1

3,182,620 5/1965 Hornberger, Sr. 112/252 1/1971 Diehm et a1. 112/252 7/1973 Jurgens 112/252 Primary ExaminerWerner H. Schroeder Attorney, Agent, or Firm-Victor J. Evans & Co.

[5 7] ABSTRACT A vacuum thread trimmer for attachment to a conventional sewing machine including a vacuum box connected to a vacuum machine with the vacuum box having a reciprocating cutter mounted therein and driven by an electric motor suspended below the sewing machine'table. The vacuum box is hollow and the cutter is hollow so that as to permit the severed thread to .pass therethrough to the suction outlet.

5 Claims, 6 Drawing Figures PATENTEDJUH 1 1 I974 SHEEI 10F 2 FIG. .1.

PATENTEDJUN 1 1 1974 3815533 SHEET 20F 2 FIG. 3.

IIIIIIYI/I/III 11/ s i VACUUM THREAD TRIMMER BACKGROUND OF THE INVENTION Field of the Invention lows the stitching operation so that all of the seams 1 being sewn pass over the vacuum thread trimmer so as to be trimmed thereby.

SUMMARY OF THE INVENTION The present invention is an improvement over my prior patent 3602172 issued Aug. 31, 1971 and entitled Vacuum Thread Trimmer." The vacuum thread trimmer of my earlier patent was located entirely above the sewing table while the vacuum trimmer of the instant invention has the major portions thereof below the sewing table withthe sewn material passing over the vacuum cutter.

The primary object of the invention is to provide a loose thread trimmer for commercial sewing machines which not only severs the loose threads but removes them from-the material being sewn.

Other objects and advantages will become apparent in the following specification when considered in the light of the attached drawings.

BRIEF DESCRIPTION-OF THE DRAWINGS FIG. 1 is a top plan view of the invention with the sewing machine shown partially broken away and in section for convenience of illustration;

FIG. 2 is a side elevation of the invention with the sewing maching shown partially broken away and in taken along the line 5-5 of FIG. 1, looking in the direction of the arrows; and

FIG. 6 is' a transverse fragmentary sectional view, taken along the line 66 of FIG. 4, looking in the direction of the arrows.-

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings in detail, wherein like reference characters indicate like parts throughout the several figures, the reference numeral 10 indicates generally a vacuum thread trimmer constructed in accordance with the invention.

The vacuum thread trimmer 10 serves as an attachment for a conventional commercial sewing machine indicated generally at 11. The sewing machine 11 includes a table surface 12 to which is attached a conventional head 13. The head 13 includesa complete sewing machine having a presser foot 14 and conventional sewing machine apparatus indicated generally at 15.

A vacuum box 16 is provided with a pair of oppositely disposed flanges l7, 18 which are adapted to be detachably secured to the head 13 and table 12 by a plurality of screws 19. An electric motor 20 is secured to the vacuum box 16 by screws 21 with its shaft 22 arranged in vertical relation and having a crank 23 on, the upper end thereof extending into the vacuum box 16.

The vacuum box 16 has a flat lower plate 24 with a pair of spaced parallel upstanding side walls 25, 26 rigidly secured thereto. A cutter bar 27 is mounted for recipr'ocation between the side walls 25, 26 on the bottom wall 24. The cutter bar 27 has a transverse slot 28 formed therein adjacent one end thereof engaging over 0 the crank 23 to reciprocate the cutter bar 27 as the motor 20 rotates. A transverse bar 29 is formed on the cutter bar 27. to assist in guiding the cutter bar 27 as it reciprocates. The cutter bar 27 has a hollow cutter blade 30 integrally formed thereon and extending through the vacuum box 16. A broad V-shaped cutting edge 31 is formed on the forward end of the cutter blade 30 for reasons to be assigned. I

A vacuum conduit 32 is secured to the vacuum box 16 in depending relation thereto and in communication therewith. A vacuum hose 33 extends from the vacuum conduit 32 to a vacuum machine (not shown).

A guide 34 is formed on the forward end of the vac- I uum box 16 to guide the threads toward the cutting edge 31 of the cutting blade 30., A generally rectangular cover 35 is detachably secured to the vacuum box 16 by screws 36 as can be seen in FIG. 1. A V-shaped slot 37 is formed in the forward end of the cover 35 to produce opposed cutting edges 38, 39' which are adapted to cooperate in a sheering action with the cutting edge 31 of the cutting blade 30. The cutting blade 30 on operation of the motor 20 reciprocates passed the cutting edges 38, 39 to sever the threads guides therebetween as the material passes overthe cover 35. Vacuum in the vacuum box 16 draws the thread through the hollow cutter blade 30 as the cutting blade 30 cuts the threads from the stitching on the garment.

The use of dual cutting edges 38, 39 and the V- shaped cutting edge 31 permits dual stitching to be trimmed such as that which is produced by a pair of sewing needles 40, 41. I

The vacuum in the vacuum box 16 is not only effective in removing the cut threads but also assist the cutting operation by drawing the loose threads into the vacuum box into a position where they can be cut by I the reciprocating cutter 30.

Having thus described the preferred embodiment of the invention it should be understood that numerous structural modifications and adaptations may be resorted to without departing from the spirit of the invention.

What is claimed is:

1. A vacuum thread trimmer attachment for sewing machines of the type having a sewing table comprising a relatively thin elongate vacuum box detachably secured to said sewing table on the upper surface thereof, an electric motor secured to one end of said vacuum box and extending through said sewing table in depending relation to said vacuum box, a vacuum conduit communicating with and depending from said vacuum box and adapted to be connected to a source of vacuum, a cutter bar, means completely within said vacuum box supporting and guiding said cutter bar for longitudinal sliding reciprocation completely within said vacuum box, means on said motor within said vacuum box cooperating with means on said cutter bar for reciprocating said cutter bar, a cover detachably secured I edges on said cutter bar are arranged in a V-shape.

4. A device as claimed in claim 3 wherein said cutter bar includes a hollow cutter blade with said cutting edges formed on said cutter blade 5. A device as claimed in claim 1 wherein the means for reciprocating said cutter bar comprises a transverse slot in said cutter bar and a crank on said motor engaged in said transverse slot for reciprocating said cutter bar on rotation of said motor. 

1. A vacuum thread trimmer attachment for sewing machines of the type having a sewing table comprising a relatively thin elongate vacuum box detachably secured to said sewing table on the upper surface thereof, an electric motor secured to one end of said vacuum box and extending through said sewing table in depending relation to said vacuum box, a vacuum conduit communicating with and depending from said vacuum box and adapted to be connected to a source of vacuum, a cutter bar, means completely within said vacuum box supporting and guiding said cutter bar for longitudinal sliding reciprocation completely within said vacuum box, means on said motor within said vacuum box cooperating with means on said cutter bar for reciprocating said cutter bar, a cover detachably secured to said vacuum box, and cutting edges on said cover at the end thereof opposite said motor cooperating with cutting edges on said cutter bar for severing thread therebetween with said severed thread removed by said source of vacuum.
 2. A device as claimed in claim 1 wherein the cutting edges on said cover are spaced apart and guide means are provided on said vacuum box between said spaced apart cutters for guiding the threads to said spaced apart cutting edges.
 3. A device as claimed in claim 2 wherein the cutting edges on said cutter bar are arranged in a V-shape.
 4. A device as claimed in claim 3 wherein said cutter bar includes a hollow cutter blade with said cutting edges formed on said cutter blade.
 5. A device as claimed in claim 1 wherein the means for reciprocating said cutter bar comprises a transverse slot in said cutter bar and a crank on said motor engaged in said transverse slot for reciprocating said cutter bar on rotation of said motor. 